Infrared emitter

Other Hardware Sensors
1

hello,
i want to ask about the infrared emitter whose shape like LED, i want to know how it works ?
if i connect it to 5v as an example will it radiate an infrared wave continuously or i have to give it the 5v as pulses to mkae it radiate every pulse ?
one more question
can i connect more than one ir receiver to arduino ? if i can then how ?

2

Your infrared emitter is an infrared LED, the only difference from an ordinary LED is that the wavelength of the light emitted is outside the range of human vision.

Don't forget to use a resistor with your LED !

Have a look here:
http://playground.arduino.cc/Code/InfraredReceivers

lookaz:
can i connect more than one ir receiver to arduino ? if i can then how ?

There's not much point in connecting more than one, why would you want to do that?

3

You have to modulate the IR LED with the same base frequency as the IR receiver. e.g. 36.7Khz or 38Khz.
Look at the receiver datasheet.
The IR receiver is designed to only pick up this frequency, and therefore it can ignore things like sunlight.
So it does not detect an IR LED supplied with DC current.

Most receivers have a wide angle of detection, but I can imagine situations that you want to use more sensors.
If you can will depend on the IR library you're using.
Leo..

4

For multiple IR receivers you need to "AND" the outputs together:

...or using transistors:

http://www.instructables.com/id/Digital-Logic-Gates-Just-Using-Transistors/

Regarding the IR emitter, you're best to test your project with a red or white LED first so you can see the light. They won't have the superior range that the infrared emitter will provide, but your IR receivers will still be able to pick up their signal at a one meter range or less.

5

Duhh. The one I'm usually using has an open collector output with mild pullup. PNA4602M
You must be able to parallel them directly.
Leo..

6

Wawa:
Duhh. The one I'm usually using has an open collector output with mild pullup. PNA4602M
You must be able to parallel them directly.
Leo..

Yes, looking at the datasheet of the Panasonic receiver and comparing to a similar Vishay receiver it seems that they should both be able to be put in parallel directly. The more complete Vishay datasheet states a 5ma output (sink) so you should be able to parallel quite a few of them together since they only have a 30K pullup.